I have a gtx 295 . Its like an oven . I toke apart the card to see the chip , and the vram , and i think my old Powercolor 4870's cooler will fit on the chip/vram , ( just have to drill some holes on the cooler) . Securing the second part of the card with a pcie backplate , and some silicon/hot glue maybe . What do you guys think about this . the other part of the card would get the full gtx 295 cooler .

Not to dismiss your creative juices or anything... but it probably won't work out well. And if you somehow manage to get it mounted without screwing up the card, it probably won't cool as well as the original cooler.

EDIT: Or are you saying you want to separate the two cards permanently and use two separate coolers on them? How will you link them together for SLI?